Method and device for measuring the velocity of an object relative to a reference

摘要

A method and apparatus for measuring the velocity of an object relative to a reference wherein the object has receivers thereon which scan a spatial function which originates from the reference. A signal is developed in each receiver, the value of which is dependent upon the position of the scanning range of the receiver relative to the reference. Signal values from a number of scanning ranges at various positions relative to the object are stored either simultaneously or cyclically at a first instant and then are compared with corresponding signal values obtained at a later time. The displacement of the spatial function relative to the object between the two scanning instants is determined and the velocity of the object is calculated from the magnitude of the displacement and the time elapsing between the scanning instants.